The Apps page, acessible from the sidebar, allows you to see a list of apps currently installed on your Hubitat Elevation hub as well as install new instances of any built-in app or already-installed custom app code. Apps are generally the way you create automations on Hubitat. (Some devices also require an app to manage their connection to the hub; examples include the Philips Hue Bridge integration, in which device management is done from the app. These are special cases.)
Examples of built-in apps include Motion Lighting, Basic Rule, and Rule Machine. Things you can do with these apps include turning lights on or off based on motion, sending notifications in response to certain events (e.g., door opens), or pretty much anything you can imagine as long as the devices you want to automate are added to your hub.
For information about built-in apps themselves, see: Apps Documentation.
To change the view type between List style and Grid style, select the appropriate icon at the top right of the Apps page. The options are list view (default for desktop):
and grid view (default for mobile):
The toggle at the top shows the current view and lets you switch between them (e.g., select List if currently in grid view to switch to list view, as in the above screenshot).
When you load the Apps page on a new hub, it may look similar to the below (just likely with fewer apps installed since you have not installed any yet). To install a new app, select Add Built-In App (labeled H below) from the upper-right corner:
This page also dispalys information about installed apps. Columns may vary depending on your display settings options (see below):
TIP: Can't find an app you installed? If you are not seeing apps that you think you should in the list, make sure you have the "parent app" expanded (select the arrow to the left of the app name to expand/collpase the list of "child apps").
Rather than removing an app you suspect may be causing an issue with your hub or device, you can simply disable it to see if the problem is resolved.
Disabling an app prevents any app code from running. Disabling a parent app will not disable child apps (but may or may not affect their operation in other ways).